Self-centering metal-to-metal seals for use with valves

Abstract

An example apparatus includes a disc-shaped valve plug having a first metallic sealing surface extending circumferentially about a peripheral edge of the valve plug. The first metallic sealing surface has a first curved profile. The example apparatus further includes a valve seat defining an orifice and having a second metallic sealing surface having a second curved profile that is complementary to the first curved profile so that the first and second metallic sealing surfaces form a metal-to-metal seal when the first and second metallic sealing surfaces are in contact.

What is claimed is: 
     
       1. An apparatus, comprising:
 a disc-shaped valve plug including a first surface, a second surface opposite the first surface, a peripheral edge located between the first and second surfaces, a plurality of bores extending between the first and second surfaces, and a first metallic sealing surface extending circumferentially about the peripheral edge, the first metallic sealing surface having a first curved profile; 
 a valve seat defining an orifice and including a second metallic sealing surface having a second curved profile, the first and second profiles being complementary so that the first and second metallic sealing surfaces form a seal when the first and second metallic sealing surfaces are in contact; and 
 a spring seat, the valve plug to be coupled to the spring seat via a plurality of fasteners, respective ones of the fasteners to be positioned in corresponding respective ones of the bores to couple the valve plug to the spring seat. 
 
     
     
       2. The apparatus as defined in  claim 1 , wherein the first and second curved profiles have respective parabolic shapes. 
     
     
       3. The apparatus as defined in  claim 1 , wherein the first curved profile has a concave shape and the second curved profile has a convex shape. 
     
     
       4. The apparatus as defined in  claim 1 , wherein the first metallic sealing surface is adjacent the second surface of the valve plug. 
     
     
       5. The apparatus as defined in  claim 1 , wherein the valve seat includes a first annular surface and a second annular surface opposite the first annular surface, the second metallic sealing surface being adjacent the first annular surface of the valve seat. 
     
     
       6. The apparatus as defined in  claim 5 , wherein the valve seat includes an inner surface, the inner surface being between the first and second annular surfaces of the valve seat, the second metallic sealing surface being adjacent the inner surface of the valve seat. 
     
     
       7. The apparatus as defined in  claim 1 , wherein the valve plug has a first central axis defined by the peripheral edge of the valve plug, the valve seat has a second central axis defined by an inner surface of the valve seat, and wherein the first and second metallic sealing surfaces align the first central axis with the second central axis when the first and second metallic sealing surfaces are in contact. 
     
     
       8. The apparatus as defined in  claim 1 , wherein the first and second metallic sealing surfaces are magnetically coupled when the first and second metallic sealing surfaces are in contact. 
     
     
       9. An apparatus, comprising:
 a disc-shaped valve plug including a first surface, a second surface opposite the first surface, a peripheral edge located between the first and second surfaces, a plurality of bores extending between the first and second surfaces, and a first metallic sealing surface extending circumferentially about the peripheral edge, the first metallic sealing surface having a first curved profile; 
 a valve seat including a second metallic sealing surface extending circumferentially about an inner surface of the valve seat, the inner surface being between a first annular surface of the valve seat and a second annular surface of the valve seat opposite the first annular surface, the inner surface and the first and second annular surfaces defining an orifice, the second metallic sealing surface having a second curved profile complimentary complementary to the first curved profile of the first metallic sealing surface; and 
 a spring seat, the valve plug to be coupled to the spring seat via a plurality of fasteners, respective ones of the fasteners to be positioned in corresponding respective ones of the bores to couple the valve plug to the spring seat. 
 
     
     
       10. The apparatus as defined in  claim 9 , wherein the first and second curved profiles have respective parabolic shapes. 
     
     
       11. The apparatus as defined in  claim 9 , wherein the first curved profile has a concave shape and the second curved profile has a convex shape. 
     
     
       12. The apparatus as defined in  claim 9 , wherein the first metallic sealing surface is adjacent the second surface of the valve plug and the second metallic sealing surface is adjacent the first annular surface of the valve seat. 
     
     
       13. The apparatus as defined in  claim 9 , wherein the first metallic sealing surface is adjacent the second surface of the valve plug and the second metallic sealing surface is adjacent the inner surface of the valve seat. 
     
     
       14. The apparatus as defined in  claim 9 , wherein the valve plug has a first central axis defined by the peripheral edge of the valve plug, the valve seat has a second central axis defined by the inner surface of the valve seat, and wherein the first and second metallic sealing surfaces align the first central axis with the second central axis when the first and second metallic sealing surfaces are in contact. 
     
     
       15. The apparatus as defined in  claim 9 , wherein the first and second metallic sealing surfaces are magnetically coupled when the first and second metallic sealing surfaces are in contact. 
     
     
       16. An apparatus, comprising:
 a first disc-shaped valve member including a first surface, a second surface opposite the first surface, a peripheral edge located between the first and second surfaces, a plurality of bores extending between the first and second surfaces, and a first sealing means for creating a seal relative to a second sealing means when the first and second sealing means are in contact, the first sealing means having a first curved profile; 
 a second valve member defining an orifice and including the second sealing means, the second sealing means having a second curved profile complementary to the first curved profile of the first sealing means; and 
 a spring seat, the first valve member to be coupled to the spring seat via a plurality of fasteners, respective ones of the fasteners to be positioned in corresponding respective ones of the bores to couple the first valve member to the spring seat. 
 
     
     
       17. The apparatus as defined in  claim 16 , wherein the first and second curved profiles have respective parabolic shapes. 
     
     
       18. The apparatus as defined in  claim 16 , wherein the first curved profile has a concave shape and the second curved profile has a convex shape. 
     
     
       19. The apparatus as defined in  claim 16 , wherein the first valve member has a first central axis defined by the peripheral edge of the first valve member, the second valve member has a second central axis defined by an inner surface of the second valve member, and wherein the first and second sealing means align the first central axis with the second central axis when the first and second sealing means are in contact. 
     
     
       20. The apparatus as defined in  claim 16 , wherein the first and second sealing means are magnetically coupled when the first and second sealing means are in contact. 
     
     
       21. The apparatus of  claim 1 , wherein respective ones of the bores are radially spaced about a central axis defined by the peripheral edge.